Month: May 2020

No visible impact yet of different COVID-19 Stage 1 strategies in Maryland

In my previous post, I was wondering if Maryland was ready to reopen, ready to enter Stage 1 of COVID-19 recovery. I also mentioned, in the end, that if Gov. Hogan announced the reopening of Maryland, he also gave counties the power to “fully” open, to be partially open or even to remain closed. You can see more info about Maryland Strong: Roadmap to Recovery: there is a map of what Counties decided.

Here is a first attempt to look at the fate of the different counties. My idea here is to set the number of cases in all counties on May 14, 2020 (start date of Stage 1) to 100% and see how counties evolve in terms of number of new daily cases.

On top of the figure below, I represent the cumulative, 7-day average (*) daily new COVID-19-confirmed cases in the different counties of Maryland. The chart at the bottom assign the number of daily cases on May 14, 2020 to 100% for each state and follow the % evolution over the next day. In this chart, the blue lines represents counties that follow Stage 1 (e.g. Garrett or Ken), the green line represents counties that partially follow Stage 1 (e.g. Anne Arundel or Frederick) and the red line represents counties that remain “closed” (Baltimore City, Charles, Prince Georges and Montgomery). The counties that remain closed are the ones that have the most cases and deaths. The chart will update automatically, even after I finish writing this post:

I must say that 6 days after Stage 1 (May 20), there is no clear trend. First, it’s normal because any downward or upward trend in number of cases will take a few day to appear (transmission or absence of transmission, incubation, decision to consult and tests, and lag in test reporting). It’s too early to see something. We will also see a confounding factor with the recent decision by the Governor to allow testing of people who do not present any symptoms (in some testing sites). Nevertheless, I was expecting to “see something”; here it just seems it’s the same.

But another reason for “not seeing anything” might be that the cases are not a relevant metric. We can already see that it is fluctuating widely every day. There are even days when less cases were reported than the day before (it might have been a data entry error on my side). The only other parameter that the MDH displays in its dashboard is the number of deaths by counties. I plotted this and it’s the same bizarre chart. How to improve this? Any idea? Don’t hesitate to comment below or to send me an email.

Update on May 24, 2020: I updated the chart of cases after Stage 1 (see above). Currently the confidence intervals (the shades) are so overlapping that differences that we could see are meaningless. Cases may not be a good metric.

I also created the same chart for deaths (see below). Here we see clearly a positive picture: in all counties that are partially open or closed, the mean number of deaths is decreasing. Note however that we are only 10 days (today is 5/24) from May 15 and this may just be a trend that existed before and not something new due to the decision to remain (partially) closed.

In counties that are in Stage 1, the mean number of deaths is actually increasing. The same comment applies: it may be too early to actually see an impact of the opening (especially deaths could be far from the case detection). Besides, the confidence intervals (the blue shades) are very wide. Hopefully things may become clearer in a few days (and for the best, given we are talking about a disease and people dying from it).

To be continued …

As usual, you’ll find other graphs on my page about COVID-19 in Maryland and the data, code and figures are on Github.
(*) the 7-day average uses the arithmetic mean of each county series over the past 7 observations.

Is Maryland ready to reopen?

A visual analysis of Governor Larry Hogan’s decision to enter Stage 1 of reopening Maryland.

(This will be a post based on a thread of tweets I posted on May 14 with updated graphs for today – one days after the start of Stage 1 – and more)

Maryland is in state of emergency since March 5, 2020 due to COVID-19. Governor Larry Hogan announced on May 14 that Maryland will “gradually reopen with flexible community-based approach” (the official declaration is here). The MD Strong plan said “a 14-day downward trajectory of benchmark metrics – or at least a plateauing of rates – is required before recovery steps can begin“. This Phase 1 started yesterday, May 15, 2020. So, are we there already?

Regarding testing … After a peak in testing (up to 8k/day) and the arrival of tests from South Korea, testing is stagnating ~ 4k/day in Maryland. The daily % of positive tests seem to stagnate ~ 22% since May started and decline a bit, ok. Despite a peak, today, we are still far from the daily number of tests we could reach with the tests from South Korea. And there is still a high percentage of daily positive cases.

Regarding hospitalizations … Thanks to a drop in acute care during the last weekend and this one, the number of patients hospitalized seems to decrease since beginning of May. This sudden drop was followed by a slight re-increase. Hopefully this will continue to decrease (even if in waves like this).

Regarding deaths … Despite a record number of daily reported deaths, early May, and wide variations in this daily metric, it seems that we are plateauing/decreasing here.

So, we can cautiously understand the decision taken, based on data. Note it’s not a total opening: the “flexible community-based approach” means that counties (the government level below the state of Maryland) are empowered to make decisions regarding actually opening or not. And some counties took that opportunity. For instance, Montgomery, Prince George’s and Charles (on the East / South-East of Maryland, surrounding Washington DC and bordering Virginia) decided to remain closed. Baltimore City also decided to remain closed. It is understandable as all these counties are among the ones with most cases and most deaths. Here is a small infographics summarizing the Stage 1 reopening:

It will be interesting to see how the next 2 weeks evolve, and especially if counties that remain closed will have a different evolution than the ones that opened.

To be continued …

As usual, you’ll find other graphs on my page about COVID-19 in Maryland and the data, code and figures are on Github.

MD counties COVID-19-specific death rate

Since a few weeks, I report the raw number of COVID-19 deaths in Maryland counties. If this gives an idea of the cumulative number of deaths – which is interesting – it doesn’t reflect the fact that some counties have more inhabitants than others. That’s why I plotted below the number of COVID-19 deaths adjusted for the population (i.e. the COVID-19-specific death rate):

(click to see more details)

Today (May 16, 2020), in terms of absolute number of deaths, Montgomery, Prince Georges and Baltimore County are the top 3 counties (this is the same for cases but not in the same order). In terms of confirmed deaths per 100,000 population, the top 3 counties are Kent, Prince Georges and Montgomery.

Rank on May 16, 2020Absolute # of COVID-19 deathsCOVID-19 deaths per 100,000 population
1Montgomery (423)Kent (66.9)
2Prince Georges (399)Prince Georges (43.5)
3Baltimore County (223)Montgomery (40.2)
4Baltimore City (192)Carroll (39.0)
5Anne Arundel (133)Charles (35.8)

Overall in Maryland so far, 1,842 deaths were reported – for a total population of 6,141,808. This gives a COVID-19-specific death rate of 29.9 per 100,000 pop. For comparison, the CDC reported a flu-specific death rate of 2 per 100,000 pop. (for the whole US, 2017) and 863.8 deaths per 100,000 pop. for all-cause deaths.

Source of Maryland County population: projections from the Maryland Department of Planning.
As usual, you’ll find other graphs on my page about COVID-19 in Maryland and the data, code and figures are on Github.

Edited a few minutes after publication to add a paragraph with the comparison with Maryland and flu; adapted the y-axis label following Michael Brown‘s comment on Twitter (thanks!); and specified the flu-specific death rate from CDC following Melissa Schweisguth‘s comment on Twitter (thanks too!).

MD counties COVID-19 cases adjusted for population

Since a few weeks, I report the raw number of COVID-19 cases in Maryland counties. If this gives an idea of the cumulative number of cases – which is interesting – it doesn’t reflect the fact that some counties have more inhabitants than others. That’s why I plotted below the number of COVID-19 cases adjusted for the population:

Evolution of COVID-19 confirmed cases in Maryland counties, adjusted and not adjusted for population, on May 11, 2020
(click to see more details)

Today (May 11, 2020), in terms of absolute number of cases, Prince Georges, Montgomery and Baltimore County are the top 3 counties. In terms of confirmed cases per 100,000 population, the top 3 counties are Prince Georges, Montgomery and Wicomico (due to a recent surge in cases).

Rank on May 11, 2020Absolute # of COVID-19 casesCOVID-19 cases per 100,000 population
1Prince Georges (9,687)Prince Georges (1,057)
2Montgomery (6,909)Montgomery (656)
3Baltimore County (3,948)Wicomico (649)
4Baltimore City (3353)Kent (555)
5Anne Arundel (2492)Baltimore City (544)

This is a lot given that, today, the average for Maryland is 401/100,000 (source: CDC) and the average for the US is 552/100,000 (source: OurWorldInData).

Source of Maryland County population: projections from the Maryland Department of Planning.
As usual, you’ll find other graphs on my page about COVID-19 in Maryland and the data, code and figures are on Github.